51 research outputs found
Breast-Lesion Characterization using Textural Features of Quantitative Ultrasound Parametric Maps
© 2017 The Author(s). This study evaluated, for the first time, the efficacy of quantitative ultrasound (QUS) spectral parametric maps in conjunction with texture-analysis techniques to differentiate non-invasively benign versus malignant breast lesions. Ultrasound B-mode images and radiofrequency data were acquired from 78 patients with suspicious breast lesions. QUS spectral-analysis techniques were performed on radiofrequency data to generate parametric maps of mid-band fit, spectral slope, spectral intercept, spacing among scatterers, average scatterer diameter, and average acoustic concentration. Texture-analysis techniques were applied to determine imaging biomarkers consisting of mean, contrast, correlation, energy and homogeneity features of parametric maps. These biomarkers were utilized to classify benign versus malignant lesions with leave-one-patient-out cross-validation. Results were compared to histopathology findings from biopsy specimens and radiology reports on MR images to evaluate the accuracy of technique. Among the biomarkers investigated, one mean-value parameter and 14 textural features demonstrated statistically significant differences (p < 0.05) between the two lesion types. A hybrid biomarker developed using a stepwise feature selection method could classify the legions with a sensitivity of 96%, a specificity of 84%, and an AUC of 0.97. Findings from this study pave the way towards adapting novel QUS-based frameworks for breast cancer screening and rapid diagnosis in clinic
Transport properties of copper phthalocyanine based organic electronic devices
Ambipolar charge carrier transport in Copper phthalocyanine (CuPc) is studied
experimentally in field-effect transistors and metal-insulator-semiconductor
diodes at various temperatures. The electronic structure and the transport
properties of CuPc attached to leads are calculated using density functional
theory and scattering theory at the non-equilibrium Green's function level. We
discuss, in particular, the electronic structure of CuPc molecules attached to
gold chains in different geometries to mimic the different experimental setups.
The combined experimental and theoretical analysis explains the dependence of
the mobilityand the transmission coefficient on the charge carrier type
(electrons or holes) and on the contact geometry. We demonstrate the
correspondence between our experimental results on thick films and our
theoretical studies of single molecule contacts. Preliminary results for
fluorinated CuPc are discussed.Comment: 18 pages, 16 figures; to be published in Eur. Phys. J. Special Topic
Recent Updates on the Melanin-Concentrating Hormone (MCH) and Its Receptor System: Lessons from MCH1R Antagonists
Melanin-concentrating hormone (MCH) is a 19-amino-acid cyclic peptide which was originally found to lighten skin color in fish that is highly conserved among many species. MCH interacts with two G-protein-coupled receptors, MCH1R and MCH2R, but only MCH1R is expressed in rodents. MCH is mainly synthesized in the lateral hypothalamus and zona incerta, while MCH1R is widely expressed throughout the brain. Thus, MCH signaling is implicated in the regulation of many physiological functions. The identification of MCH1R has led to the development of small-molecule MCH1R antagonists that can block MCH signaling. MCH1R antagonists are useful not only for their potential therapeutic value, but also for understanding the physiological functions of the endogenous MCH system. Here, we review the physiological functions of the MCH system which have been investigated using MCH1R antagonists such as food intake, anxiety, depression, reward, and sleep. This will help us understand the physiological functions of the MCH system and suggest some of the potential applications of MCH1R antagonists in human disorders
Optimization of insect cell based protein production processes - online monitoring, expression systems, scale-up
Due to the increasing use of insect cell based expression systems in research and industrial recombinant protein production, the development of efficient and reproducible production processes remains a challenging task. In this context, the application of online monitoring techniques is intended to ensure high and reproducible product qualities already during the early phases of process development. In the following chapter, the most common transient and stable insect cell based expression systems are briefly introduced. Novel applications of insect cell based expression systems for the production of insect derived antimicrobial peptides/proteins (AMPs) are discussed using the example of G. mellonella derived gloverin. Suitable in situ sensor techniques for insect cell culture monitoring in disposable and common bioreactor systems are outlined with respect to optical and capacitive sensor concepts. Since scale-up of production processes is one of the most critical steps in process development, a conclusive overview is given about scale up aspects for industrial insect cell culture processes
Heritability and Relationship among Durum Wheat Quality Traits Using a Recombinant Inbred Lines Population
Traits related to seed quality have an important role in production of durum wheat. To estimate the heritability of protein content, semolina content, Zeleny number, seed hardness, SDS, dry and fresh gluten content, gluten index, and also to investigate the relationship of these traits in durum wheat, a recombinant inbred lines (RILs) population including 94 recombinant inbred lines (F10), two parents (Ac. Navigator and G9580B-FE1C) and four controls (Diper, Preion and PI10235 varieties and a local variety “Ajr”) were evaluated. This experiment was carried out in the Research Farm of Shahrekord University, Shahrekord, Iran, using a triple lattice design.. Results showed that frequency distribution for gluten index was bimodal and for the rest of the traits was normal. This indicated the two-genes control and quantitative inheritance of these traits in the population,respectively. Transgressive segregation was observed for all the traits. The calculated heritability for protein content, seed hardness, SDS and semolina content was in the low range of 11.4-24.7%. For fresh and dry gluten and Zeleny number, it was 45, 36.2 and 37.1%, respectively. For gluten index, it was high (76.6%). The genetic correlation coefficient between protein content and Zeleny number was positive and high (r= 0.98), which indicates the suitability of this trait as a criterion for protein content. The results of path analysis for semolina, as the main feature in pasta production, based on genetic correlation coefficients, showed that the highest negative direct effect was related to Zeleny number the highest positive effect was related to protein content, which indicated the importance of these traits in explaining the semolina yield
Reactive Crystallization of Brushite under Steady State and Transient Conditions:Â Modeling and Experiment
Gestational diastolic hypertension with gene mutation-related pheochromocytoma positive at (18)F-DOPA PET/CT: Diagnostic and therapeutic implications.
A 38-year-old woman referred to the hypertension centre of Rovigo Hospital in January 2012 for uncontrolled hypertension despite treatment with long-acting nefidipine (30mg once daily). She reported a history of gestational diastolic hypertension, arose during her three pregnancies, respectively in 2004, 2007 and 2008. In 2008, during the latter pregnancy, abdominal ultrasound performed for suspected cholelithiasis incidentally detected a right adrenal mass. The patient denied symptoms attributable to hyper- 17
tensive crisis. In 2009 a magnetic resonance imaging (MRI) was performed, showing a solid right adrenal lesion (Fig. 1a), with oval shape and sharp margins. Twenty-four-hour urinary catecholamines, 24-h cortisoluria, renin and aldosterone serum levels were normal. In 2012 a positron emission tomography (PET)with the radiolabelled amino acid-based radiopharmaceutical L-6-[18F]fluoro-3,4-25 dihydroxyphenylalanine (18F-DOPA), combined with computed tomography (CT),was performed. 18F-DOPAPET/CT images showed an oval area of increased pathological uptake of the tracer in the lodge of right adrenal gland,with axial diameter of 3.5 cmandwith maximal standardized uptake value of 40.0. Family medical history showed that the 65-year-old father of the patient was hypertensive and in 1993 underwent left adrenalectomy for a benign nodule.
33 Among the instrumental investigations carried out on the patient, 24-h ambulatory blood pressure measurement showed uncontrolled hypertension with systolic\u2013diastolic average values of 137.2/93.6mmHg during 24 h, normal blood pressure variability, circadian rhythmwith non-dipper pattern and nocturnal hypertension, and mean heart rate of 90 bpm. No signs of cardiac, vascular or renal organ damage were detected. Among the urinary metabolites of catecholamines, a marked increase in nor-metanephrine levels was detected (5_mol/24-h, normal values 0.57\u20131.90). MRI and 18F-DOPA PET/CT findings enabled a diagnosis of pheochromocytoma. Further imaging studies, such as neck and pancreas ultrasonography, excluded multiple endocrine neoplasms. After anti-hypertensive treatment with amlodipine (5mg once 46 a day) and doxazosin (4mg once a day), the patient underwent right adreanalectomy via videolaparoscopy. Histological examination showed a typical pheochromocytoma of the adrenal medulla without necrosis or atypia, with compression of adjacent cortical and focal areas of recent haemorrhage. Genetic analysis showed a mutation of the associated factor X gene (MAX). MAX gene mutation, only recently identified in literature, is associated with family forms of pheochromocytoma; it is transmitted through the paternal way and appears to be associated with an increased risk of malignancy. In conclusion, pheochromocytoma is a rare catecholamine producing endocrine tumour. Even more it rarely occurs during pregnancy, but it deserves some special considerations in view of high rate of maternal and foetal mortality that in some surveys reached 40\u201350%.2 Early and timely diagnosis is required, as the neoplasm can be removed at any stage of pregnancy. It is there- 60
fore recommended to use evaluation of urinary metanephrines and particularly 18F-DOPA PET/CT, that allows to diagnose pheochromocytomas even when not detectable by other scintigraphic methods and with multiple spread.3 Furthermore, genetic analysis
can identify some rare genetic mutations associated with family forms of pheochromocytoma, reaching early diagnosis also in the relatives, avoiding fatal complications
Radioiodine treatment of non-toxic multinodular goitre : effects of combination with lithium
Purpose: This study aimed to evaluate the effects of radioiodine ( 131I), alone or in combination with lithium, on thyroid volume and the prevention of radioiodine-induced thyrotoxicosis. This is the first clinical trial including only patients with multinodular goitre, normal TSH values and negative anti-thyroid auto-antibodies at baseline. Methods: Eighty consecutive patients were randomised to receive 131I plus lithium (group I+L) or 131I alone (group I). Thyroid ultrasonography and biochemical analyses were performed at baseline and at 1, 3, 6, 12 and 24 months after treatment. Results: At 1-4 weeks after treatment, 131I-induced hyperthyroidism was observed in 58.8% of patients and was prevented by lithium administration. A low incidence of hypothyroidism (19%) was recorded at 24 months, whereas up to 44% of patients developed anti-thyroid antibodies. A significant reduction in thyroid volume was observed after 131I, with a mean decrease of 47.2% (median 48.2%) at 24 months, without differences between the groups. Moreover, it was shown that the decrease in thyroid volume after 131I was also due to the significant shrinkage of thyroid nodules. Conclusion: This demonstrates that adjunctive lithium is able to reduce radioiodine-induced hyperthyroidism. Therefore, such treatment appears to be safe in older patients and those with underlying cardiovascular disease. In the present large series, 131I therapy was demonstrated to be highly effective in reducing thyroid and nodular volume even in patients treated with low 131I doses (2.5 MBq/ml of thyroid tissue), further supporting the view that radioiodine therapy represents a real alternative to surgery
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