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1.
Micro-CT can play an important role in preclinical studies of cardiovascular disease because of its high spatial and temporal resolution. Quantitative analysis of 4D cardiac images requires segmentation of the cardiac chambers at each time point, an extremely time consuming process if done manually. To improve throughput this study proposes a pipeline for registration-based segmentation and functional analysis of 4D cardiac micro-CT data in the mouse. Following optimization and validation using simulations, the pipeline was applied to in vivo cardiac micro-CT data corresponding to ten cardiac phases acquired in C57BL/6 mice (n = 5). After edge-preserving smoothing with a novel adaptation of 4D bilateral filtration, one phase within each cardiac sequence was manually segmented. Deformable registration was used to propagate these labels to all other cardiac phases for segmentation. The volumes of each cardiac chamber were calculated and used to derive stroke volume, ejection fraction, cardiac output, and cardiac index. Dice coefficients and volume accuracies were used to compare manual segmentations of two additional phases with their corresponding propagated labels. Both measures were, on average, >0.90 for the left ventricle and >0.80 for the myocardium, the right ventricle, and the right atrium, consistent with trends in inter- and intra-segmenter variability. Segmentation of the left atrium was less reliable. On average, the functional metrics of interest were underestimated by 6.76% or more due to systematic label propagation errors around atrioventricular valves; however, execution of the pipeline was 80% faster than performing analogous manual segmentation of each phase.  相似文献   
2.
Clinical Oral Investigations - The study evaluates the effect of adding graphene-Ag nanoparticles (G-AgNp) to a PMMA auto-polymerizing resin, with focus on antibacterial activity, cytotoxicity,...  相似文献   
3.
Hepatic steatosis is a frequently encountered disease in medical practice and it has a great importance due to the potential evolution towards cirrhosis. The clinical and laboratory evaluation has a quite reduced positive predictive value. On the other hand, a series of imaging techniques may be used for the diagnosis and quantification of steatosis: magnetic resonance imaging, computerized tomography, and not least, ultrasonography. The contribution of each of the afore mentioned methods in the diagnosis of the hepatic steatosis will be discussed.  相似文献   
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The hamartomatous polyps in Peutz-Jeghers syndrome may have malignant potential. To differentiate between hamartomatous and adenomas polyps, vascular characterization can be assessed using noninvasive procedures, such as contrast-enhanced ultrasound (CEUS). The neo-angiogenic characteristics of colorectal adenomas and carcinomas are expressed as an anarchic vascular pattern observed on CEUS. Using CEUS in a patient with Peutz-Jeghers syndrome, we describe for the first time the vascularization of a hamartomatous colonic polyp that exhibits a hierarchy branching pattern.  相似文献   
6.
Baca-Estrada ME  Foldvari M  Ewen C  Badea I  Babiuk LA 《Vaccine》2000,18(17):1847-1854
The development of non-invasive methods for the delivery of proteins through the permeability barriers, such as the intact skin, will greatly facilitate the administration of human and veterinary vaccines. In the present study we used recombinant Pasteurella haemolytica leukotoxin (Lkt) and hen egg lysozyme (HEL) as model antigens to investigate the ability of transdermal administration of vaccine antigens to induce humoral and cellular responses in mice and to assess the immunomodulatory effects of IL-12 on these antigen-specific immune responses. Mice were immunized by the transdermal route with Lkt or HEL formulated in a novel lipid-based biphasic delivery system (BPDS). Transdermal delivery of Lkt or HEL induced strong polarized Th2 responses characterized by enhancement of antigen-specific IgG1 antibody subclass and predominant induction of antigen specific IL-4 over IFN-gamma in spleen and draining lymph nodes cells. Animals immunized by topical application of formulations containing antigen and IL-12 developed significantly lower antibody titres without significant changes in IL-4 or IFN-gamma secreting cells (SC) in the draining lymph nodes or spleen cells. Our results indicated that application of antigens formulated in BPDS induced antigen-specific immune responses. Furthermore, incorporation of IL-12 to the vaccine formulation influences the induction of antibody responses induced by transdermal immunization. We demonstrated the feasibility of using this technology for the development of non-invasive methods of vaccine administration.  相似文献   
7.
A first derivative spectrometric method has been developed for the determination of the 5-fluorouracil and N1(2'-furanidyl)uracil related substances and degradation products of tegafur. The wavelengths selected for the determination of 5-fluorouracil and N1(2'-furanidyl)uracil were 298 and 288 nm, respectively. At this wavelength, the calibration graphs between the amplitude of the signals and the concentration of each compound were linear up to 24.75 mg l(-1) for 5-fluorouracil and up to 20.20 mg l(-1) for N1(2'-furanidyl)uracil. The detection limits were 0.40 and 0.050 mg l(-1) for 5-fluorouracil and N1(2'-furanidyl)uracil, respectively. The method is simple and rapid and does not require any preliminary treatment of the sample. The method was validated.  相似文献   
8.
Chronic pancreatitis is a disease with a potentially severe evolution due to the pain altering life quality and to the possibility of causing exocrine and endocrine pancreatic insufficiency. Ultrasound represents the main imaging technique to be used in this disease since the identification of pancreatic calcifications has diagnostic significance. Endoscopic ultrasound may sometimes identify parenchymal changes facilitating diagnosis in the early stages of chronic pancreatitis when transabdominal ultrasound and endoscopic retrograde cholangiopancreatography show normal situations or non-characteristic changes.  相似文献   
9.
BackgroundLupus erythematosus (LE) is a heterogeneous disease with broad clinical spectrum from cutaneous to visceral and systemic inflammation. IL-17 isoforms (IL-17A and IL-17F) are proinflammatory cytokines with unclear implications in lupus erythematosus pathogenesis. In this study we focused upon IL-17 in normal and modified lupus skin with a correlative study between local and serological expression.Material and methods89 subjects were recruited and divided in 5 groups—10 patients with psoriasis (disease control group), 13 healthy controls, 26 with discoid chronic lupus (DLE), 23 with systemic lupus erythematosus (SLE) and 17 with subacute lupus erythematosus (SCLE). Blood samples and skin punched-biopsy specimens were performed. Serum IL-17A, IL-17F, and IL-23 concentrations were determined by ELISA. Skin IL-17A and CD4 expression were evaluated by immunohistochemistry.ResultsImmunohistochemical expression of IL-17A was higher in DLE, SCLE and SLE patients than in negative control subjects (all p < 0.05). Serum IL-17A concentrations were higher in DLE and SLE patients than in negative controls (p < 0.05). Serum IL-17A levels were similar in SCLE and negative controls (p > 0.05). Serum IL-17F concentrations were higher in DLE, SCLE and SLE patients than in healthy controls (all p < 0.05). In DLE, SCLE, SLE patients and healthy controls we observed comparable levels of IL-23 (p > 0.05). Serum anti Ro antibodies correlate with IL-17A+ lymphocytes from SCLE lesion and SLE normal skin (all p < 0.05).ConclusionIL-17 isoforms (IL-17A and IL-17F) are implicated in SLE but also in DLE and SCLE immunopathogenesis.  相似文献   
10.
The Mouse Biomedical Informatics Research Network (MBIRN) has been established to integrate imaging studies of the mouse brain ranging from three-dimensional (3D) studies of the whole brain to focused regions at a sub-cellular scale. Magnetic resonance (MR) histology provides the entry point for many morphologic comparisons of the whole brain. We describe a standardized protocol that allows acquisition of 3D MR histology (43-microm resolution) images of the fixed, stained mouse brain with acquisition times <30 min. A higher resolution protocol with isotropic spatial resolution of 21.5 microm can be executed in 2 h. A third acquisition protocol provides an alternative image contrast (at 43-microm isotropic resolution), which is exploited in a statistically driven algorithm that segments 33 of the most critical structures in the brain. The entire process, from specimen perfusion, fixation and staining, image acquisition and reconstruction, post-processing, segmentation, archiving, and analysis, is integrated through a structured workflow. This yields a searchable database for archive and query of the very large (1.2 GB) images acquired with this standardized protocol. These methods have been applied to a collection of both male and female adult murine brains ranging over 4 strains and 6 neurologic knockout models. These collection and acquisition methods are now available to the neuroscience community as a standard web-deliverable service.  相似文献   
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