395 research outputs found
Budd-Chiari Syndrome Imaging Diagnosis: State of the Art and Future Perspectives
Budd-Chiari syndrome (BCS) is a rare hepatic vascular disorder defined by the presence of partial or complete impairment of hepatic venous drainage in the absence of right heart failure or constrictive pericarditis. Several conditions can lead to BCS, from hypercoagulable states to malignancies. Primary BCS is the most common subtype, and usually bartends hypercoagulability states, while secondary BCS involves tumor invasion or extrinsic compression. A combination of clinical and imaging features leads to the diagnosis of BCS, including (1) direct signs: occlusion or compression of the hepatic veins and/or inferior vena cava, and the presence of venous collaterals; (2) indirect signs: morphological hepatic changes with caudate lobe enlargement; inhomogeneous enhancement, and hypervascular nodules. From a clinicopathological point of view, two forms of BCS can be distinguished: acute and subacute/chronic BCS, although asymptomatic and fulminant forms are also possible. Acute presentations are rare, and symptoms include hepatomegaly, ascites, and hepatic insufficiency. Subacute/chronic forms are the most common presentation, with dysmorphic liver and variable degrees of fibrosis deposition. Patients with chronic BCS can develop benign regenerative nodules (large regenerative nodules or FNH [Focal Nodular Hyperplasia]-like lesions), but are also at a higher risk of hepatocellular carcinoma (HCC). The radiologist role is therefore fundamental in both diagnosis and surveillance of BCS. The aim of this review is to present all clinical and imaging signs that can help to reach the diagnosis of BCS, with their clinical significance, providing tips and tricks for the cross-sectional diagnosis of this condition
Amine-Rich Carbon Dots as Novel Nano-Aminocatalytic Platforms in Organic Synthesis
The development of novel and effective metal-free catalytic systems, which can drive value-added organic transformations in environmentally benign solvents (for instance, water), is highly desirable. Moreover, these new catalysts need to be harmless, easy-to-prepare, and potentially recyclable. In this context, amine-rich carbon dots (CDs) have recently emerged as promising nano-catalytic platforms. These nitrogen-doped nanoparticles, which show dimensions smaller than 10 nm, generally consist of carbon cores that are surrounded by shells containing numerous amino groups. In recent years, organic chemists have used these surface amines to guide the design of several synthetic methodologies under mild operative conditions. This Concept highlights the recent advances in the synthesis of amine-rich carbon dots and their applications in organic catalysis, including forward-looking opportunities within this research field
Advanced magnetic resonance imaging of cortical laminar necrosis in patients with stroke
Purpose: The aim of this study was to assess the novel advanced magnetic resonance imaging findings of acute stage cortical laminar necrosis developing after complicated cardiovascular or abdominal surgery. Materials and methods: This institutional review board-approved study included patients with postoperative stroke due to cortical laminar necrosis imaged with magnetic resonance in the acute stage. Brain magnetic resonance imaging examinations were obtained on a 3T magnetic resonance scanner within 48 hours of the neurological symptoms, including diffusion-weighted images (b value, 1000 s/mm2) and arterial spin labelling using a pseudo-continuous arterial spin labelling method in four patients. Conventional and advanced magnetic resonance images were analysed to assess the imaging features in acute stage cortical laminar necrosis. Results: The final population consisted of 14 patients (seven men and seven women, mean age 61 years, range 32–79 years) diagnosed with stroke and acute phase cortical laminar necrosis. All the patients presented with cortical lesions showing restricted diffusion on diffusion-weighted images and hypointensity on the apparent diffusion coefficient map. Cortical hyperintensity on T2-weighted or fluid-attenuated inversion recovery images was found in three (21%) and six (43%) patients, respectively. Reduced perfusion was noted in three out of four patients imaged with arterial spin labelling, while in one case no corresponding perfusion abnormality was noted on the arterial spin labelling maps. Arterial spin labelling abnormalities were much more extensive than diffusion restriction in two patients, and they were associated with a poor outcome. Conclusion: Cortical hyperintense abnormalities on diffusion-weighted imaging may be the only sign of developing cortical laminar necrosis injury. The acquisition of arterial spin labelling helps to identify perfusion alterations and the extension of the ischaemic injury
Structural properties of food proteins underlying stability or susceptibility to human gastrointestinal digestion
Shining Light on Carbon Dots: New Opportunities in Photocatalysis
Photocatalysis is an emerging field that exploits light-absorbing catalysts to yield transformations not even achievable in the dark. Considering the drawbacks of metal-based photocatalysts, Carbon Dots (CDs) recently emerged as suitable green alternatives for different photocatalytic reactions. These carbon nanoparticles are easy to prepare, non-toxic and potentially recyclable. Moreover, CDs usually display core-shell structures which are highly tunable via synthetic and post-synthetic strategies. This Concept Article focuses on the recent advancements in the CD-based photocatalysis, highlighting the link between their superficial and core composition and their resulting photo-redox abilities, and giving future perspectives on their application in cutting-edge area
Tailoring the Chemical Structure of Nitrogen-Doped Carbon Dots for Nano-Aminocatalysis in Aqueous Media
Amine-rich carbon dots (NCDs) have become promising nano-aminocatalytic platforms in organic synthesis. These nanomaterials can be effectively produced through straightforward bottom-up approaches using inexpensive nitrogen-containing molecular precursors as a starting material. However, to date, there is still a limited understanding of how the molecular features of these precursors affect the catalytic activity of the resulting nanoparticles. This study concerns the production of a new family of NCDs, which use l-arginine and different alkyl diamines as starting materials. The surface amines of all these NCDs were comprehensively characterized, thus allowing us to provide a correlation between the structural features of the nanoparticles and their catalytic performance with a selected amino-catalyzed organic transformation. Importantly, the most active nano-aminocatalysts, namely, NCDs-3, were then used as a basis for the formation of a wide variety of functionalized organic compounds in water under mild reaction conditions
Proteomic and immunological characterization of a new food allergen from hazelnut (Corylus avellana).
Hazelnuts (Corylus avellana) are one of the most common sources of life-long IgE-mediated food allergies. In this study, we investigated the IgE-reactivity pattern of children with hazelnut allergy (N=15) from Regione Campania, located in Southern Italy, and addressed proteomic strategies for characterizing IgE-binding proteins. For all of the patients (15/15), the predominant IgE-reactive component was a minor ~55kDa protein not previously described. Similar to the hazelnut 11S globulin Cor a 9 allergen, the immunoreactive protein consisted of two subunits linked via a disulfide bridge. In contrast to Cor a 9, only the 20.7kDa alkaline subunit exhibited IgE-affinity. The immunogenic subunit was purified by a two-step chromatographic procedure, but peptide mass fingerprinting was unsuccessful in identifying it, due to the incompleteness of the annotated hazelnut genome. Several tryptic peptides were de novo sequenced by tandem mass spectrometry and showed a high degree of homology with the 11S globulin storage proteins from other seeds, some of which have already been reported as food allergens. The structural characterization suggests that the new putative allergen is a divergent isoform of the hazelnut 11S globulin. These results provide a new platform for developing innovative diagnostic and therapeutic intervention plans.
BIOLOGICAL SIGNIFICANCE:Over the years, at least five proteins have been reported as potential food hazelnut allergens. The predominance of specific allergens appears to be strictly related to the geographical origin of the allergic subjects. The complex patterns of the IgE-reactivity of hazelnut storage proteins result in a poor diagnostic and prognostic accuracy. In the perspective of a component-resolved "molecular approach" to the hazelnut allergy we investigated the immune-reactivity patterns to hazelnuts of 15 patients (14 in the pediatric age range) from Region Campania, located in Southern Italy. For all the patients the predominant IgE-reactive component was a minor ~55kDa protein not previously annotated in either protein or genomic databases. The putative allergen was isolated, partially characterized by MS/MS de novo sequencing and appears to be an isoallergen of the hazelnut 11S globulin Cor a 9. Like this latter, the immunoreactive protein consisted of two subunits linked via a disulfide. In contrast to Cor a 9, only the 20.7kDa alkaline subunit exhibited IgE-affinity, in analogy to 11S allergens from other seeds (pistachio, cashew, soybean). We believe that the application of combined immunochemical and proteomic strategies to characterize the new food allergen could be of interest for the readers of Journal of Proteomics. In addition, the results of this study have functional worth in providing a new platform to plan innovative diagnostic and therapeutic intervention approaches to treat hazelnut allergy
Resting-State Functional Connectome in Patients with Brain Tumors Before and After Surgical Resection
Purpose: High-grade glioma surgery has evolved around the principal belief that a safe maximal tumor resection improves symptoms, quality of life, and survival. Mapping brain function has been recently improved by resting-state functional magnetic resonance imaging (rest-fMRI), a novel imaging technique that explores networks connectivity at “rest.” Methods: This prospective study analyzed 10 patients with high-grade glioma in whom rest-fMRI connectivity was assessed both in single-subject and in group analysis before and after surgery. Seed-based functional connectivity analysis was performed with CONN toolbox. Network identification focused on 8 major functional connectivity networks. A voxel-wise region of interest (ROI) to ROI correlation map to assess functional connectivity throughout the whole brain was computed from a priori seeds ROI in specific resting-state networks before and after surgical resection in each patient. Results: Reliable topography of all 8 resting-state networks was successfully identified in each participant before surgical resection. Single-subject functional connectivity analysis showed functional disconnection for dorsal attention and salience networks, whereas the language network demonstrated functional connection either in the case of left temporal glioblastoma. Functional connectivity in group analysis showed wide variations of functional connectivity in the default mode, salience, and sensorimotor networks. However, salience and language networks, salience and default mode networks, and salience and sensorimotor networks showed a significant correlation (P uncorrected <0.0025; P false discovery rate <0.077) in comparison before and after surgery confirming non-disconnection of these networks. Conclusions: Resting-state fMRI can reliably detect common functional connectivity networks in patients with glioma and has the potential to anticipate network alterations after surgical resection
Brain core temperature of patients before and after orthotopic liver transplantation assessed by diffusion weighted imaging thermometry
Comparative analysis of eliciting capacity of raw and roasted peanuts: the role of gastrointestinal digestion
This study investigated the simultaneous impact of food matrix and processing on the food allergy eliciting capacity of peanuts in a physiologically relevant context. Whole raw and roasted peanuts were subjected to in vitro digestion combining the harmonized oral-gastric-duodenal digestion models with brush border membrane enzymes (BBM) to simulate the jejunal degradation of peptides. SDS-PAGE and HPLC analysis showed that roasting increased digestibility of peanuts and this trend was even more evident after BBM degradation. The eliciting properties of raw and roasted peanuts were assessed by Rat Basophil Leukemia assay in the presence of sera from peanut-allergic patients. As general features, the BBM digestion reduced allergenicity of roasted peanuts compared to the raw counterpart, suggesting that intestinal peptidases effectively contribute to further destroy specific domains of peanut allergens. These findings provide new and more realistic insights in the stability of peanut allergens within their natural matrix
- …