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关键词： miRNA expression   Wilms tumor   Histology   Prognosis  

摘要： Introduction Wilms tumor is the most common renal malignancy in children and difficult to differentiate from other paediatric abdominal tumors radiologically, necessitating an invasive procedure for diagnosis. Previous studies have shown the potential role of miRNA as biomarkers for diagnosis, histological subtyping and prognosis. In this study, we are exploring the role of miRNA in the histological subtyping of Wilms tumor in the Indian population. Materials and methods A total of 15 cases of Wilms tumor were evaluated for global miRNA expression analysis by microarray. Total RNA was extracted from fresh frozen tumor and miRNA expression analysis was performed using Agilent platform. Unsupervised clustering was done to analyse the data. Results Using unpaired student T test, top 10 significantly differentially expressed miRNA were selected which could differentiate among different histological subtypes by unsupervised hierarchical clustering and principal component analysis. The presence of necrosis, heterologous differentiation led to change in miRNA expression profile and led to a distinct cluster formation. Conclusions A panel of 5 miRNAs (miR1, 133b, 299-3p, 499a-5p, 491-3p) could differentiate among different histological subtypes of Wilms tumor, thus avoiding an invasive procedure in children, however, further confirmation using real time PCR analysis will be needed.

关键词： 微分方程-数学模型  

ISBN: (纸本)9787030708434

摘要： 这是一本微分方程通识性读本，帮助读者建立微分方程基本框架，带领读者初探微分方程研究之门。作业答案、程序源代码、电子课件、拓展阅读文献等资源齐备，对初学者特别友好。作为方程方向的学生，这本书确实给我一条切入科研的探索路径，给了我学习方法。——网友这本书不错，关键有详细作业解答，可以跟着仿作，仔细体会作者研究思路，相当于手把手教了，就冲着作业答案，也值得入手。——网友……

关键词： Left-dominant arrhythmogenic cardiomyopathy   Cardiac magnetic resonance   Ventricular arrhythmias  

摘要： Cardiac magnetic resonance (CMR) findings suggesting a suspected left-dominant arrhythmogenic cardiomyopathy (LDAC) may be difficult to distinguish from those related to previous myocarditis;however, especially in patients with ventricular arrhythmias (VA) with ECG morphology consistent with a left ventricle (LV) origin differential diagnosis is fundamental. Aim of the study was to identify potential imaging features at CMR specific for LDAC diagnosis. Between January 2011 and December 2019, we enrolled 15 consecutive stable patients with a recent diagnosis of significant VA and ECG morphology consistent with a LV origin, detection of potential LV arrhythmic substrate at CMR and undergoing a clinically-indicated LV endomyocardial biopsy showing tissue abnormalities consistent with the diagnosis of LDAC. From the same CMR-endomyocardial biopsy registry, a second group of 30 consecutive patients who underwent CMR and biopsy with a histological diagnosis of previous myocarditis were identified. (1) Subepicardial LGE at the level of the posterolateral wall of the LV was detected in 13 cases of LDAC vs. 21 cases of myocarditis;(2) fat infiltration, and particularly subepicardial posterolateral fat infiltration, was found in almost all LDAC patients vs. one myocarditis only (p < 0.01). (3) No differences in other CMR findings or in any clinical or echocardiographic parameters were found between patients with a biopsy consistent with LDAC vs. myocarditis. In patients with significant VA and ECG morphology consistent with a LV origin, the presence of morpho-functional involvement of the subepicardial layer of LV posterolateral wall at CMR (LGE, fat infiltration, wall dyskinesis) supports LDAC diagnosis.

关键词： Triceps surae   Differential muscle activation   Automatic postural response   Feet positioning  

摘要： The ankle plantar flexor muscles act synergistically to control quiet and dynamic body balance. Previous research has shown that the medial (MG) and lateral (LG) gastrocnemii, and soleus (SOL) are differentially activated as a function of motor task requirements. In the present investigation, we evaluated modulation of the plantar flexors' activation from feet orientation on the ground in an upright stance and the ensuing reactive response to a perturbation. A single group of young participants (n = 24) was evaluated in a task requiring initial stabilization of body balance against a backward pulling load (5% or 10% of body weight) attached to their trunk, and then the balance was suddenly perturbed, releasing the load. Four feet orientations were compared: parallel (0 degrees), outward orientation at 15 degrees and 30 degrees, and the preferred orientation (M = 10.5 degrees). Results revealed a higher activation magnitude of SOL compared to MG-LG when sustaining quiet balance against the 10% load. In the generation of reactive responses, MG was characterized by earlier, steeper, and proportionally higher activation than LG-SOL. Feet orientation at 30 degrees led to higher muscular activation than the other orientations, while the activation relationship across muscles was unaffected by feet orientation. Our results support the conclusion of task-specific differential modulation of the plantar flexor muscles for balance control.

关键词： Lamprey   Erythrocytes   Liver   Prespawning starvation   Mitogen-activated protein kinases  

摘要： The study was designed to identify the types of mitogen-activated protein kinases (MAPKs) in erythrocytes and liver tissues of river lamprey Lampetra fluviatilis and monitor the changes in protein expression levels of found enzymes on the course of prespawning starvation (from November to the end of May). Immunoreactivity of the native and phosphorylated forms of ERK1/2, JNK and p38 was examined in the cytosolic and membrane cell fractions. Both lamprey erythrocytes and liver were found to highly express ERK1/2 and JNK, whereas only trace amounts of p38 were revealed in hepatic tissues. ERK1/2 was identified in cytosolic and membrane fractions, whereas JNK and p38 were predominantly cytosolic enzymes. Total cellular amounts of ERK1/2 and phospho-ERK1/2 in both erythrocytes and liver tissues appeared to be relatively stable on the course of prespawning starvation. However, before spawning ERK1/2 translocated from cytosol to membranes, with partial decline of its cytoplasmic expression being compensated by increases in membrane-bound pool. Immunoreactivity of cytoplasmic JNK, phospho-JNK and p38 were stable from November to March, but sharply decreased before spawning exhibiting almost negligible levels in May, which suggests the depletion of their cellular fractions. Most probably, ERK1/2 plays more important role in mediating adaptive responses of erythrocytes and liver tissues to conditions of natural starvation and maintenance of cell viability before spawning and death of animals in May.

关键词： different spatial resolutions   differential phase contrast CT   dual-energy CT   human observer model   material decomposition   performance evaluation  

摘要： Purpose The purpose of this study is to evaluate and compare the quantitative material decomposition performance of the dual-energy CT (DECT) and differential phase contrast CT (DPCT) via numerical observer studies. Methods The electron density (rho e$\rho _{{\rm e}}$) and the effective atomic number (Zeff$Z_{{\rm eff}}$) are selected as the decomposition bases. The image domain based decomposition algorithms with certain noise suppression are used to extract the rho e$\rho _{{\rm e}}$ and Zeff$\text{Z}_{{\rm eff}}$ information under three different spatial resolutions (0.3 mm, 0.1 mm, and 0.03 mm). The contrast-to-noise-ratio (CNR) and the numerical human observer model which is sensitive to the noise textures are investigated to compare the quantitative imaging performance of DECT and DPCT under varied radiation dose levels. Results The model observer results show that the DECT is superior to DPCT at 0.3 mm spatial resolution (300 mm object size);the DECT and DPCT show similar quantitative imaging performance at 0.1 mm spatial resolution (100 mm object size);and the DPCT outperforms the DECT by approximately 1.5 times for the 0.3 mm sized imaging target at 0.03 mm spatial resolution (30 mm object size). Conclusions In conclusion, the DECT would be recommended to obtain rho e$\rho _{{\rm e}}$ and Zeff$Z_{{\rm eff}}$ for the low spatial resolution quantitative imaging applications such as the diagnostic CT imaging. Whereas, the DPCT would be recommended for ultra high spatial resolution imaging tasks of small objects such as the micro-CT imaging. This study provides a reference to determine the most appropriate quantitative X-ray CT imaging method for a certain radiation dose level.

摘要： Background: Transplantation of allogenic Langerhans islets (ISL) has been employed as an alternative to pancreas transplantation to provide endogenous supply of insulin and treat hypoglycemia unawareness in type 1 diabetes. Nevertheless, the process of islets isolation exposes the islets to hypoxia and other aggressive conditions that results in the recover of less than half of the islets present in the pancreas. Several studies demonstrated that co-culturing islets with mesenchymal stromal cells (MSC) before implantation enhances islets survival and function and this effect is mediated by cytokines. However, it remains unclear if the profile of cytokines secreted by MSC in co-culture with islets changes upon the type of co-culture: direct and indirect. Materials and Methods: In 3 series of experiments with human islets of 3 different donors, we compared the levels of a panel of cytokines measured in the supernatant of ISL cultured alone, Wharton Jelly MSC (WJMSC) cultured alone, direct co-culture of ISL-WJMSC and indirect co-culture using a permeable transwell membrane to separate ISL and WJMSC. Results: Comparing the profile of cytokines secreted by islets alone with islets in direct co-culture with WJMSC, we found higher expression of IL1b, IL17, IF gamma, IL4, IL10, IL13, Granulocyte-macrophage colony-stimulating factor (GMCSF) and Leptin, in the supernatant of the co-cultures. In contrast, when comparing islets cultured alone with islets in indirect co-culture with MSC, we found no significant differences in the levels of cytokines we analyzed. Conclusion: Direct contact between human WJMSC and pancreatic islets is required for elevated expression of a range of immune cytokines, including both those considered inflammatory, and anti-inflammatory.

关键词： C3S   Thermal analysis   Crystalline phases development   Endodontic cement  

摘要： Endodontic calcium silicate-based cement is the most used materials in root-end filling and/or repairing perforations. However, the relatively high cost associated with these cement is a drawback that necessitates improvements in their manufacturing process through the development of alternatives. This study used differential scanning calorimetry (DSC) and high-temperature X-ray powder diffraction observations of the tricalcium silicate (C3S) crystalline phase to identify and quantify important parameters of hydration reactions such as the degree of hydration. A C3S reference was prepared with pure chemical reagents to develop a novel biomaterial variety of calcium silicate-based cement which was predefined to preserve the significant properties and clinical applications typical of calcium silicates. A methodology of cycled synthesis was used to obtain almost pure, highly crystalline C3S phase. With temperatures that can reach 1450-1500 degrees C, the thermal processing of the mixture of raw materials gives rise to thermochemical reactions of the formation of the main phases: 2CaO center dot SiO2 (C2S), 3CaO center dot SiO2 (C3S), and 3CaO center dot Al2O3 (C3A). The formation of the C3S phase is aided by the fusion of calcium aluminates (C3A). The use of Al2O3 and MgO as liquid phase-forming agents and the stabilization of the phases in cooling, allowed the liquid phase to provide the greatest precipitation of the C3S solid phase of interest. The X-ray diffraction confirmed the formation of the highly C3S crystalline phase in the material after cooling at the end of the five thermal cycles. The results obtained indicated that such a material could be derived through bottom-up synthesis routes that aim to attain the proper balance between the C3S phase and the use of other cementitious materials.