Enhancing the discrimination accuracy between metastases, gliomas and meningiomas on brain MRI by volumetric textural features and ensemble pattern recognition methods

Three-dimensional (3D) texture analysis of volumetric brain magnetic resonance (MR) images has been identified as an important indicator for discriminating among different brain pathologies. The purpose of this study was to evaluate the efficiency of 3D textural features using a pattern recognition system in the task of discriminating benign, malignant and metastatic brain tissues on T1 postcontrast MR imaging (MRI) series. The dataset consisted of 67 brain MRI series obtained from patients with verified and untreated intracranial tumors. The pattern recognition system was designed as an ensemble classification scheme employing a support vector machine classifier, specially modified in order to integrate the least squares features transformation logic in its kernel function. The latter, in conjunction with using 3D textural features, enabled boosting up the performance of the system in discriminating metastatic, malignant and benign brain tumors with 77.14%, 89.19% and 93.33% accuracy, respectively. The method was evaluated using an external cross-validation process; thus, results might be considered indicative of the generalization performance of the system to "unseen" cases. The proposed system might be used as an assisting tool for brain tumor characterization on volumetric MRI series.     

Elliptical magnetic resonance spectroscopic imaging with GRAPPA for imaging brain tumors at 3 T

Magnetic Resonance Spectroscopic Imaging (MRSI) is a technique for imaging spatial variation of metabolites and has been very useful in characterizing biochemical changes associated with disease as well as response to therapy in malignant pathologies. This work presents a self-calibrated undersampling to accelerate 3D elliptical MRSI and an extrapolation-reconstruction algorithm based on the GRAPPA method. The accelerated MRSI technique was tested in three volunteers and five brain tumor patients. Acceleration allowed larger spatial coverage and consequently, less lipid contamination in spectra, compared to fully sampled acquisition within the same scantime. Metabolite concentrations measured from the accelerated acquisitions were in good agreement with measurements obtained from fully sampled MRSI scans.     

The comparison of the proton dose distribution calculated with the treatment planning system and measured with alanine detectors in the eye phantom irradiated under therapeutic conditions

The paper describes the applicability of commercially available alanine detectors produced by Synergy Health for verification of the dose distribution calculated by the treatment planning system (TPS) used in proton eye radiotherapy – Eclipse Ocular Proton Planning (EOPP) program, version 8.9.06, Varian Medical Systems. The TPS-planned dose distribution at selected points in the eye phantom is compared to the dose registered by alanine detectors at these points during a simulated therapeutic irradiation at the proton eye radiotherapy facility in the Henryk Niewodniczanski Institute of Nuclear Physics (IFJ PAN), Krakow, Poland. The phantom was irradiated to obtain, a typical for choroidal melanoma, fraction dose of 15 CGE (13,64 Gy) at the tumor location. The dose registered with alanine pellets located inside the simulated tumor volume demonstrates a good agreement with the TPS-planned dose. The typical for proton radiotherapy, steep dose fall-off outside the treated area is registered by the alanine pellets however, it is difficult to assess it quantitatively, because the dose related EPR signal is registered from the entire pellet volume.     

Functional magnetic resonance cholangiography with Gd-EOB-DTPA: A study in healthy volunteers

Purpose

To describe the patterns of bile distribution in the biliary tree, duodenum, jejunum, and stomach, and to determine the gallbladder ejection fraction (GBEF) by using functional magnetic resonance cholangiography (MRC) with gadolinium-ethoxybenzyl-diethylenetriamine penta-acetic acid (Gd-EOB-DTPA) in healthy volunteers.

Materials and Methods

Forty subjects were included in this study. After conventional MRC, pre-fatty meal MRC (PRFM) was obtained at 30, 40, 50, and 60 min after contrast agent injection. Then, post-fatty meal MRC (POFM) was obtained every 10 min for 1 h. We assessed the PRFM and POFM for opacification of contrast agent in the first- and second-order intrahepatic ducts (IHDs) and the common bile duct (CBD). Contrast agent opacification in the cystic duct was assessed, and the percentage volume of contrast agent filling in the gallbladder (GB) was calculated on PRFM. We calculated the GBEF and assessed the presence of contrast agent in the GB, duodenum, jejunum, and stomach.

Results

Thirty-six (90%) subjects showed grade 3 CBD opacification (visible contrast and well-defined bile duct border) on 60-min PRFM. Thirty-four (85%) subjects showed grade 3 first-order IHD opacification on 60-min PRFM. All (100%) subjects showed cystic duct opacification of contrast agent, and the average percentage volume of contrast agent filling in the GB was 68.81% ± 16.84% on 60-min PRFM. The GBEF at 30-min POFM was 35.00% ± 18.26%. Ten (25%) subjects had no contrast agent in the stomach and small bowel on all PRFMs. Twelve (30%) subjects had contrast medium in the stomach on PRFM and/or POFM.

Conclusions

Functional MRC with Gd-EOB-DTPA can allow determining the distribution of bile in the biliary tree and small intestine, as well as the GBEF.     

Equivalent cross-relaxation rate imaging positively correlates with pathological grade and cell density of adipocytic tumors

Objective

Equivalent cross-relaxation rate imaging (ECRI) is an MRI technique used to evaluate qualitative changes in protein-water interactions. We aimed to prospectively evaluate the utility of ECRI for classification of adipocytic tumors.

Materials and Methods

Institutional Review Board approval was obtained and all patients provided informed consent. Study participants included 40 patients with adipocytic tumors who were diagnosed with lipomas (n = 22), atypical lipomatous tissue/well-differentiated liposarcoma (ALT/WDL; n = 9), myxoid/round cell liposarcoma (MyL; n = 6), and dedifferentiated liposarcoma (DDL; n = 3), and 20 control patients for whom subcutaneous fat in the buttock or thigh was analyzed.

Results

Mean ECR values of lipomas, ALT/WDL, and subcutaneous fat were low, and those of MyL and DDL were high. Mean ECR values of MyL and DDL were significantly higher than those of ALT/WDL. The cut-off value was 5.1%. There was a positive correlation between ECR value, pathological grade, and cell density in adipocytic tumors.

Conclusion

The ECR value positively correlates with pathological grade and cell density of adipocytic tumors. Our findings suggest that ECRI is a useful method for preoperative evaluation of adipocytic tumors.     

A Comprehensive Review on the Benefits and Problems of Curcumin with Respect to Human Health

Curcumin is the most important active component in turmeric extracts. Curcumin, a natural monomer from plants has received a considerable attention as a dietary supplement, exhibiting evident activity in a wide range of human pathological conditions. In general, curcumin is beneficial to human health, demonstrating pharmacological activities of anti-inflammation and antioxidation, as well as antitumor and immune regulation activities. Curcumin also presents therapeutic potential in neurodegenerative, cardiovascular and cerebrovascular diseases. In this review article, we summarize the advancements made in recent years with respect to curcumin as a biologically active agent in malignant tumors, Alzheimer’s disease (AD), hematological diseases and viral infectious diseases. We also focus on problems associated with curcumin from basic research to clinical translation, such as its low solubility, leading to poor bioavailability, as well as the controversy surrounding the association between curcumin purity and effect. Through a review and summary of the clinical research on curcumin and case reports of adverse effects, we found that the clinical transformation of curcumin is not successful, and excessive intake of curcumin may have adverse effects on the kidneys, heart, liver, blood and immune system, which leads us to warn that curcumin has a long way to go from basic research to application transformation.     

Pyridinium-Substituted Tetraphenylethylenes Functionalized with Alkyl Chains as Autophagy Modulators for Cancer Therapy

Tuning autophagy in a controlled manner could facilitate cancer therapy but it remains challenging. Pyridinium-substituted tetraphenylethylene salts (PTPE 1 — 3 ), able to target mitochondria and disrupt autophagy after forming complexes with albumin, are reported. Mitochondrion affinity and autophagy-inducing activity are improved by prolonging the length of alkyl chains in PTPE 1 – 3 . PTPE 1 – 3 demonstrate proautophagic activity and a mitophagy blockage effect. Failure of autophagosome–lysosome fusion in downstream autophagy flux results in cancer cell death. Moreover, fast formation of complexes of PTPE 1 – 3 with albumin in blood can facilitate biomimetic delivery and deep tumor penetration. Efficient tumor accumulation and effective tumor suppression are successfully demonstrated with in vitro and in vivo studies. PTPE 1 – 3 salts exhibit dual functionality: they target and image mitochondria because of aggregation-induced emission effects and they are promising for cancer therapy.     

Pyridinium‐Substituted Tetraphenylethylenes Functionalized with Alkyl Chains as Autophagy Modulators for Cancer Therapy

Tuning autophagy in a controlled manner could facilitate cancer therapy but it remains challenging. Pyridinium‐substituted tetraphenylethylene salts (PTPE 1 — 3 ), able to target mitochondria and disrupt autophagy after forming complexes with albumin, are reported. Mitochondrion affinity and autophagy‐inducing activity are improved by prolonging the length of alkyl chains in PTPE 1 – 3 . PTPE 1 – 3 demonstrate proautophagic activity and a mitophagy blockage effect. Failure of autophagosome–lysosome fusion in downstream autophagy flux results in cancer cell death. Moreover, fast formation of complexes of PTPE 1 – 3 with albumin in blood can facilitate biomimetic delivery and deep tumor penetration. Efficient tumor accumulation and effective tumor suppression are successfully demonstrated with in vitro and in vivo studies. PTPE 1 – 3 salts exhibit dual functionality: they target and image mitochondria because of aggregation‐induced emission effects and they are promising for cancer therapy.     

Enhanced MRI of tumors utilizing a new nitroxyl spin label contrast agent

Nitroxyl spin labels have been shown to be effective in vivo contrast agents for magnetic resonance imaging (MRI) of the central nervous system, myocardium, and urinary tract. A new pyrrolidine nitroxyl contrast agent (PCA) with better resistance to in vivo metabolic inactivation than previously tested agents was studied for its potential to enhance subcutaneous neoplasms in an animal model. Twenty-two contrast enhancement trials were performed on a total of 15 animals 4-6 weeks after implantation with human renal adenocarcinoma. Spin echo imaging was performed using a .35 T animal imager before and after intravenous administration of PCA in doses ranging from 0.5 to 3mM/kg. The intensity of tumor tissue in the images increased an average of 35% in animals receiving a dose of 3 mM/kg. The average enhancement with smaller doses was proportionately less. Tumor intensity reached a maximum within 15 min of injection. The average intensity difference between tumor and adjacent skeletal muscle more than doubled following administration of 3 mM/kg of PCA. Well-perfused tumor tissue was more intensely enhanced than adjacent poorly perfused and necrotic tissue.     

胃肠道正常组织与相应肿瘤组织结构的FTIR光谱研究

本文用傅里叶变换红外显微光谱对一系列胃肠道（食道、胃、结肠）肿瘤组织和相应正常组织的冰冻切片进行了研究。结果显示，所有肿瘤组织的光谱基本一致。而正常组织的光谱按１４００－９５０ｃｍ＾－１区域的特点可分为三类。对光谱中蛋白质酰胺Ｉ带曲线拟合的结果表明，正常组织和肿瘤组织中蛋白质的二级结构有着很大的差别。